Automatic ingot tongs



Patented Aug. 14, 1945 AUTOMATIC INGOT TONGS James Hutson Hopkins andEdgar Homer Kendall, Alliance, Ohio Application October 23, 1943, SerialNo. 507,400

2 Claims.

The invention relates to automatic tongs, and more particularly toautomatic tongs adapted for suspension from the end of a crane cable andfor being raised and lowered thereby for'automatically engaging anarticle or releasing an engaged article. More particularly, theinvention relates to automatic ingot tongs for handling hot steel ingotsand the like.

In the processing of steel ingots and the like,

vertical heating furnaces are frequently used,-

and a vertical heating furnace for relatively long articles, such asingots, may include an inner elongated article'receiving verticaltubular compartment, which may be as deep as 15 feet and have an upperopening with removable covers.

1 The elongated article, such as a steel ingot,

is lowered into and raised out of the vertical compartment through theupper opening by automatic tongs suspended from the hook on the end of acrane cable, the tongsfengaging and releasing the upper end of the ingotor the like, by raising and lowering operations of the cable.

After the ingot or the like has been heated to the required extent, thetemperature in the vertical compartment may be as high as 2400 F.

It is, therefore, necessary that suitable, tongs for handling an ingotor the like into and out of a vertical heatingfurnace must be not onlyautomatic in operation, but must alsobe capa-Z ble of automaticoperation at a temperature of: as high as 2400 F. a I

It is also desirable that such automatic ingot tongs adapted for hightemperature use should have as long a life as possible, and should be.of such construction as to permit rapid as" wellas economicalmanufacture and maintenance:

Automatic tongs for handling, ingots-and-the like available prior to thepresent improvements have not met all of, the foregoing enumeratedrequirements to the degree desired 'by' users of; automatic tongs. r

The objects of the present invention include the provision of improvedautomatic tongs par-; ticularly adapted for handling ingots duringheating operations in vertical heating furnaces,: and which areoperative in-an improved manner by relative straight line movement ofthe principal parts of the automatic tongs controlling the relativepositions and movements of the tong so that they may be manufactured andmaintained with facility and economy.

Further objects of thepresent invention include the provision ofimproved automatic tongs in which the parts are arranged for positive,certain, and repeating cyclical operation. The foregoing and otherobjects are obtained by the automatic tongs, apparatus, parts,improvements, combinations, and sub-combinations which comprise thepresent invention, and the nature of which is set forth in the followinggeneral statement, and preferred embodiments of which together withtheir mode of use are set forth in the following description, and whichare particularly and distinctly pointed out and set forth in theappended claims forming a part hereof. l

The nature of the present invention may be stated in general terms asincluding in automatic tongs, upper head means for suspension from therods operatively connecting the tong levers with the upper head means,and automatic push and pull actuated cyclically engaging and releasinglatch and catch means operative between the upper head means and thetong lever mounting means for controlling the action of the tang leversby successive lifting connections and nonlifting associations of thehead means with the tong lever mounting means.

When the tong levers are in gripping position, as on opposite sides ofan ingot, they are suspended by the rods from the upper head means.

When the gripped ingot is located at the desired position, the automatictongs are lowered so that the lower tong lever mounting means seats uponthe upper end of the ingot, and the.

upper head means are further lowered to engage the upper latch means onthe upper head means with the lower catch means on the lower tongmounting means, in such a position that the tong levers are locked inthe open position.

When it is desired to pick up another object,

such as another ingot, thetongs with the levers in the locked openposition are lowered so that the tong lever mounting means seats on theupper end of the ingot to be picked up, after which the upper head meansare further lowered and are illustrated in the accompanying drawingsforming a part hereof, in which Figure 1 is a fragmentary elevation Viewwith portions broken away and illustrated in longitudinal axial sectionof one embodiment of the improved automatic tongs, the tong grippingbits and other parts being shown in their relative positions when thetong gripping bits are maintained open; a

Fig. 2 a similar view illustrating the relative positions of the partsof the improved automatic tongs at the end of the first push actionnecessary for releasing the tong gripping bits from the locked openposition;

Fig. 3 a similar view illustrating the relative" positions of the partsof the improved automatic tongs when the tong gripping bits-are ingripping and lifting positions;

Fig. 4 a transverse sectional view as on line 4-4, Fig. 3; and t Fig. 5a fragmentary longitudinal axial sectional view, illustrating a secondembodiment of the improved automatic push and pull actuated cyclicallyreleasing latch and catch means adapted for being included in improvedautomatic tongs which are otherwise similar to the automatic tongs ofFigs. 1 to 4 inclusive.

Similar numerals refer to similar parts throughout the drawings.

The improved automatic tongs are indicated generally by ID, and includeupper head means indicated generally by l I, lower tong lever mountingmeans indicated generallyby i2, tong levers indicated generally by; l3aand l3!) pivotally mounted on the mounting means I 2, andtong leveractuating rods indicated generally by Ma and Mb operatively connectingthe tong levers [3b and Ba respectively with the upper head means II. vr

The upper head means H and the lower tong lever mounting means l2furthermore include in operative association with each other improvedautomatic push and pull actuated cyclically engaging and releasing latchand catch means indicated generally by l5 for controlling the ac-.

tion of the tong levers l3a and lv3bby successive lifting connectionsand non-lifting associations of the head II with thetong lever mountingmeans 12.

The upper head means I l includes as shown a pair of spaced preferablyparallel upwardly elongated and taperingouter plates 16, the upper apexendsl'l of'which are spaced and connected by lift pin means indicatedgenerally by l8. Below the lift pin means l8 and parallel therewith, 'astop bolt 19 extends between the plates l6 and through oppositeapertures therein, and is secured therein by the usual bolt head andnut.

The longitudinal axis of the tongs i0 is indicated by the dot-dash lineY, and at equal disshown perpendicularto the plates l6. Each of thetrunnions, 22a and 225 has formed therein a slide bore '23at rightangles to the axis of its bearings, each slide bore 23 being preferablycylindric. The upper ends. of 'thepreferably. cylindric rods Ma and Nbextend through the slide bores 23 of the trunnions 22a and22b'respecproved automatic tongs of the present invention tively. Upperend portions of each rod Ida. and Mb are externally threaded, and nuts24a and 242) are screwed respectively on the upper threaded ends of therods Ma and Mb above their respective slide trunnions 22a and 22b.

' The tong lever mounting means l2 includes preferably as shown a yokeindicated generally by 25 having an upper tubular shank 26 whose bore isco-axial with the axis Y and having an outwardly flanged lower end 21from opposite sides of which, preferably parallel with the head plates[6, depend inverted spaced T oke legs 28. Each inverted T yoke leg 28includes an upper elongatedzstem 29 extending downwardly from one sideof the shank flange 21 and terminatin in a crossbar 30.

At equal distances from opposite sides of the longitudinal center planeextending through longitudinal axis Y and perpendicular to the platesI6, the crossbars 30 of the yoke legs 28 have formedtherein oppositepairs of registering apertures in which are located oppositeends offulcrum pins 3la and 31b. 'Each fulcrum pin 3m and 3 lb preferablyincludes at each end a threaded outer end 32 extending through one ofthe mounting apertures in one of the crossbar 30 and beyond the outerface thereof, where a se curing nut 33 is screwedthereon.

, The tong levers l3aand B1) are preferably angled as shown. The tonglever l3a includes a longer upper arm 34a located between the yoke legs28 and having formed therein a bearing aperture through'which thefulcrum pin 31a extends. From the pin Sla, the arm 34a extends towardsthe pin 3Ibwhere the arm 34 terminates above the pin 3lb in a clevis 35ahaving registering apertures formedin its U side members. I

The lower end of the rod. Mb has secured thereon a sleeve cap 3617 fromthe lower end of Which extends a tongue .311) between the U side arms ofthe clevis 35a, the tongue 31b having formed therein an apertureregistering with-the clevis arm apertures, and the registering clevisarm apertures and the tongue aperture are connected bya pin 38.

The tonglever .arm- 34a extends a short distance beyond the outer sideof the fulcrum pin 3la to a curved apex 390. from which depends ashorter tong lever arm 40a near the lower end of which is located atapered aperture 41a in the central plane parallel with the plates l6and passing through the longitudinal axis Y. The tapered aperture Ma hasits larger end adjacent the axis Y and receives the tapered end of atong bit 4211 having a pointed inwardly directed conical gripping head43a.

Similarly'the tong lever l3b includes a longer upper arm 34b locatedbetween the yoke legs 28 and having formed therein a bearing aperturethrough which the fulcrum pin 3H2 extends. From the pin 3lb, the arm 34bextendsalong one side'of the arm 34:: towards the pin am, where the arm34b terminates above the pin 31a in a clevis 351) having registeringapertures formed in its U side members.

The lower end of the rod Ma has secured thereon a sleeve cap 36a fromthe lower end of which extends a tongue 31a. having formed therein anaperture registering with the clevis arm apertures, and the registeringclevis arm apertures and the tongue apertures are connected by a pin 38.

The tong lever arm 34!) extends a short distance from the outer side ofthe fulcrum pin (ill) to a curved apex 392) from which depends a shorterThe automatic cyclically engaging andi release ing'latch and catch meansI5 operative between the head H and the tong lever mounting means I2includes in the head -r I I slide bearing and latch mounting meansindicated generally by 44 and comprising spaced elongated rectangularconnecting plates .45 each having a. longitudinal axis in thelongitudinal centerplane passing through the longitudinal axis Y andperpendicular to the plates I6, and each connecting plate 45 having anouter face in abutment With the inner face of one of the plates I6. Theconnecting plates 45 are thus located between the head lift plates I 6.

Between the connecting plates 45 there is secured as by welding alongitudinally extending slide guide. and latch mounting preferablycylindric tube 46 having its longitudinal axis coinciding with thelongitudinal axis Y. At each pposite side of its longitudinal axis, eachplate 45 has formed therein a row of longitudinally spaced aperturesregistering with a similar row of apertures in the abutting plate I6 andwith the directly opposite rows of apertures in the other plate 45 andits abutting plate I6. Through each set of registering apertures in theplates I6 and 45, a removable connecting bolt 41 extends, each bolt 41having on the outer opposite sides of plates I6 a usual bolt head andnut.

At the upper end of the tube 46 is secured a cap 48 from which dependwithin the bore of tube 46 a plurality of latch hooks 49 which will bedescribed in greater detail hereinafter.

Upon the upwardly extending yoke shank 26 is telescoped a slide tube 50which extends upwardly, and slidably fits in the bore of the guide andlatch mounting tube 46. Within the upper end of the bore of theslidetube 50 is located a catch or detent preferably as shown in theform of a cylindric tube fitting in the bore of the tube 50 and havingat its upper end a downwardly sloping inwardly extending frusto-conicalcatch or detent flange 52. At thelower end of the bore of the tube 5| isfitted a cylindric connector plug 53, and the connector plug 53 and thetubes 5| and 50 have formed therein registering apertures through whichextends a connector pin 54.

The plug 53 extends below the lower extremity of tube 5| and is providedco-axial with the axis Y with an internally threaded socket in which isscrewed the upper threaded end of the shank of a tie bolt 55. The yokeshank 26 is provided with a central aperture and the shank of the-tiebolt 55 extends through the central aperture of the yoke shank 26, andthere is preferably provided between the lower head of the bolt 55 andthe lower end of the shank 26 a centering washer 56. Within the bore ofthe catch tube 5 I, there is slidably located a preferably tubular andpreferably externally cylindric cam 51. l

Each of the latch hooks 49 includes as shown an upper elongated springstem 58 depending from the cap 48 and a lower hook end 59 extendingoutwardly from the lower end of the stem 58 away from the axis Y in adirection generally perpendicular thereto for engagement anddisengagement'of its upper hook face with the lower frustog conicalhookttace' of the flange 52. The lower camiace 60. of each h0Qk"nd'5a'iS curvedand preferably spherical. "llhepreferably tubular ,cam 51:longitudinally jslidable in the hereof the tube 5| between the flange 52and the pl 3 includes at 'itsup er end an inwardly extending annularcam. flange 6| which in cross sectionhas a ridge contour in; a planepassingthrough the axis Y. the apex of the ridge being adjacentthelaxisY andbeing preferably flattened.- t 1 Accordingly, when thelower spherical camface fill and the hook ends of the latch hooks-49 arepushed, into ,thetubular or sleeve cam Blythe hookends 359. on thespring stems 58 will be sprung inwardly toward the axis Y by the cammingac:

tion of the spherical ,faces .60 being pusheddowlll wardly through thethroatof the invva iily exv tending annular ridge cam flange 6|.

In operation the improved automatic tongs ID are usually suspended froma crane cable attached at its lower end to the lift pin means l8 of theupper head means II. The crane cable, not shown, is a part of a usualcrane and is raised and lowered by the usual operation of the crane toraise and lower the automatic tongs.

When the automatic tongs I0 have theirparts in the relative positionshown in'Fig. l, the tong levers 311 and 1 3b and their gripping bits aremaintained open, the latch hooks 49 being engaged beneath thefrusto-conical catch or-dee tent flange 52.

When the automatic tongs II] are lowered with the tong levers in theirlocked open position so that the tong lever mounting means I2 strikesagainst the upper end of an object to be lifted, such as an ingot, thetong lever mounting means I2 is pushed with respect to the upper headmeans II, and the head means II is dropped with re-. spect to the levermounting means I2, so that the latch hooks 49 are pushed into thetubular or sleeve cam 51 below the cam flange 6|, as

shown in Fig. 2. l

Upon next raising the head means I2, the sleeve cam 51 is raised by thehook ends 59 of the latch hooks 49 till the upper end of the sleeve cam51 abuts against the lower end of the catch or detent annular flange 52,when the hook ends 59 are sprung inwardly from the axis Y and displacedfrom engaging position with respect to the catch 52 and are permitted tobe pulled upwardly through the annular catch or detent flange 52, so

that the parts of the automatic tongs I I) may assume the gripping orclosed positions of the tong levers and gripping bits shown in Fig. 3.

In Fig. 5 is illustrated a second embodiment of the improved push andpull actuated cyclically engaging and releasing latch and catch meansadapted for being included in improved tongs which otherwise are similarto the automatic The latch and.

tongs in Figs. 1 to 4 inclusive. catch means of Fig. 5 are indicatedgenerally by M5 and generally are similar to the latch and catch meansI5, with the exception that in the latch and catch means I I5 the latchhooks I49 inwhich may at any time properly under theUIlit'ed Statespatent lawsbe set forth in the claims hereof'or originating herein,- andthe elements of any such claims are intended to include their reasonable, mechanical and functional equivalents;

1'. In automatic tongs and the like, upperhead means, lower tong levermounting meansftong levers pivotally mounted on the-mountingmeans, tonglever suspension and actuating rods operatively connecting the tonglevers with the upper head means, and push and pull actuated cyclicallyengaging and releasing latch an'd catch means operative between theupper head means and the lower tong lever mounting means and controllingthe positions of the to'ng levers, and each rod having a lower pivotalconnection with one of the levers and an upper slidable and pivotalconnection with the head means.

tion with the head means.

"JAMES HUTSON HOPKINS.

EDGAR HOMER

